1. Field
An aspect of the present disclosure relates generally to a semiconductor electronic device and a manufacturing method thereof and, more particularly, to a three-dimensional semiconductor device and a manufacturing method thereof.
2. Description of the Related Art
A nonvolatile memory device maintains stored data even when a power supply to the device is interrupted. Recently, as the pace of improvement of the degree of integration of a two-dimensional non-volatile memory device in which memory cells are formed in a single layer on a substrate has reached a plateau, a three-dimensional structure has been proposed for nonvolatile memory devices in which memory cells are vertically stacked on a substrate.
Typically, a three-dimensional nonvolatile memory device includes interlayer dielectric layers and gate electrodes, which are alternately stacked, and vertical channel layers penetrating the interlayer dielectric layers and the gate electrodes. Memory cells are stacked along the channel layers. In a typical manufacturing process of a three-dimensional non-volatile memory device, a plurality of oxide layers and a plurality of nitride layers are alternately stacked, and the plurality of nitride layers are replaced with a plurality of conductive layers, thereby forming stacked gate electrodes.
However, generally, replacing the nitride layers with conductive layers is rather cumbersome. Moreover, a reaction gas generated during the replacement process may remain in the stacked structure which may damage peripheral layers. Therefore, certain characteristics of the memory device may be degraded.